Early WIP render of the Tartarus, as I decided it should look. The ship is around 12km long. The REKT areas are near the back, right in front of the engines. Decks are vertical, not horizontal like Star trek. Hangar is on the underside of the ship and holds roughly one million CASKETs.
It's an early image, and I'll likely add a lot more detail later, but it's good enough for now. I'd like to hear feedback before I continue.

Huh. That's fairly similar to how I imagined it to look. For some reason my brain kept insisting it should look like the Battlestar Galactica. I don't even like that show. So I altered my mental image of it, and it's fairly similar to what you produced.

Not really. Let's say, from the image, it's about 3 km wide. That's 3000 m * 13000 m = 39 000 000 m², or 39 m² per CASKET, which should be enough. Added to that, they can multiple that surface quite a bit, since it's perfectly possible to store them above eachother when they're not in use.

A New Challenger wrote:LOL. Though I have to say, 1 million sounds a bit...hyperbolic. How wide is it? Plus you need room for dropships and all that other stuffs. Just putting the thought out there.

There's enough room. The Tartarus can comfortably hold maybe 20 million people, research labs, engineering areas, etc. That's comfortably holding. It actually holds twice that number, with three quarters of it being prisoners cramped into less than half the ship in tiny cells (30 million) which also sounds like a ton, but when you're gathering thousands of criminals from around the galaxy daily as you go from system to system, you can gather up 10 million or so in about a year. (did the math for that too.) The Tartarus grows its own nutritional paste (don't ask) for the 29mil "normal" inmates, and purchases higher-quality foodstocks for staff and REKT crew members. It's basically a city in a ship, centered around a massive prison. There's plenty room enough for all the dropships involved, with the many three-deck-high hangar areas on the "underside" (Tartarus technically doesn't have a true "top" side). And Tartarus absolutely cannot land. Under any circumstances. It lacks the heat shielding for it or any of the necessary equipment for in-atmosphere flight - and they'd be hard-pressed to find a space station large enough to comfortably accommodate it.